Vantaggi
If you are starting out, it's good. I learnt a lot from my supervisor in terms of improving my skills- it was like being in school, good snacks, young company constantly growing. Same tasks every day, which can be fun and stable if you want it.
Svantaggi
Management style is not for everyone. Constantly reminding you of what you did wrong, and what you can do better rather than positive reinforcing you, as if they want you to feel inadequate and never comfortable. Micro-managing your time. Forget ever feeling ok leaving for a bathroom break and not freaking out when your boss messages you asking where you are. They want to know what you are doing every second of the day. Management normally takes credit for your ideas without even mentioning you at all. Management will pick favourites, if you are social and get along with them on a personal level especially. Lots of Over Time without pay or much interest from management in improving that. It's just expected. Expectations to live to work because managers do so.